login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A322084 Square array A(n,k), n >= 1, k >= 0, read by antidiagonals: A(n,k) = Sum_{d|n, n/d==1 (mod 4)} d^k - Sum_{d|n, n/d==3 (mod 4)} d^k. 5

%I #15 Jan 07 2024 15:52:15

%S 1,1,1,1,2,0,1,4,2,1,1,8,8,4,2,1,16,26,16,6,0,1,32,80,64,26,4,0,1,64,

%T 242,256,126,32,6,1,1,128,728,1024,626,208,48,8,1,1,256,2186,4096,

%U 3126,1280,342,64,7,2,1,512,6560,16384,15626,7744,2400,512,73,12,0,1,1024,19682,65536,78126,46592,16806,4096,703,104,10,0

%N Square array A(n,k), n >= 1, k >= 0, read by antidiagonals: A(n,k) = Sum_{d|n, n/d==1 (mod 4)} d^k - Sum_{d|n, n/d==3 (mod 4)} d^k.

%H Andrew Howroyd, <a href="/A322084/b322084.txt">Table of n, a(n) for n = 1..1275</a> (first 50 antidiagonals)

%H <a href="/index/Ge#Glaisher">Index entries for sequences mentioned by Glaisher</a>

%F G.f. of column k: Sum_{j>=1} j^k*x^j/(1 + x^(2*j)).

%e Square array begins:

%e 1, 1, 1, 1, 1, 1, ...

%e 1, 2, 4, 8, 16, 32, ...

%e 0, 2, 8, 26, 80, 242, ...

%e 1, 4, 16, 64, 256, 1024, ...

%e 2, 6, 26, 126, 626, 3126, ...

%e 0, 4, 32, 208, 1280, 7744, ...

%t Table[Function[k, SeriesCoefficient[Sum[j^k x^j/(1 + x^(2 j)), {j, 1, n}], {x, 0, n}]][i - n], {i, 0, 12}, {n, 1, i}] // Flatten

%o (PARI) T(n,k)={sumdiv(n, d, if(d%2, (-1)^((d-1)/2)*(n/d)^k))}

%o for(n=1, 10, for(k=0, 8, print1(T(n, k), ", ")); print); \\ _Andrew Howroyd_, Nov 26 2018

%Y Columns k=0..12 give A002654, A050469, A050470, A050471, A050468, A321829, A321830, A321831, A321832, A321833, A321834, A321835, A321836.

%Y Cf. A109974, A279394, A279396, A285425, A322081, A322082, A322083.

%K nonn,tabl

%O 1,5

%A _Ilya Gutkovskiy_, Nov 26 2018

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 24 20:08 EDT 2024. Contains 371963 sequences. (Running on oeis4.)